[spark] Pin Scala to 2.13.17 under spark4 profile

Spark 4.1.1 is built against Scala 2.13.17 and depends on APIs added in
that patch (e.g. MurmurHash3.caseClassHash$default$2). Paimon's global
scala213.version is still 2.13.16 for the spark3 / Flink lines, so
override scala.version directly inside the spark4 profile to avoid
NoSuchMethodError during Spark 4.1 Catalyst execution.

Author: kerwin-zk

pom.xml

@@ -433,7 +433,9 @@ under the License.
                 <target.java.version>17</target.java.version>
                 <antlr4.version>4.13.1</antlr4.version>
                 <scala.binary.version>2.13</scala.binary.version>
-                <scala.version>${scala213.version}</scala.version>
+                <!-- Spark 4.1.1 is built against Scala 2.13.17; force the same stdlib here so that
+                     `MurmurHash3.caseClassHash$default$2` and related APIs resolve at runtime. -->
+                <scala.version>2.13.17</scala.version>
                 <paimon-spark-common.spark.version>4.1.1</paimon-spark-common.spark.version>
                 <paimon-sparkx-common>paimon-spark4-common_2.13</paimon-sparkx-common>
                 <arrow.version>18.1.0</arrow.version>